My windows 10 is 64 bit. It is installed in c:\Program Files\ActiveHome Pro. I didn't try running as Administrator, I'll do that. I've been using ActiveHome Pro for many years but recently the CM15A ActiveHome Pro USB went bad and I'm waiting for a replacement to arrive. I downloaded a new copy of the software and was trying to set on/off times for the recirculating water pump. It used to work very well but now I can't save the settings.

Good to know, glad you got it to save.You may wish to move the ActiveHome Pro folder to the root (C:\) as there are other issues with Win10 and applications run from Program Files (x86) and it seems Microsoft adds more security to that folder with each new update.